In a computer system, the working temperature is a big concern for the computer system can work stable or not. If the working temperature of the computer system is over to a limit, the chip in the computer system may not be able to process data correctly, or the computer system may crash, or even the hardware of the computer system may be damaged. Therefore, a temperature detecting system, for detecting the working temperature of the chip, is usually equipped in the computer system.
FIG. 1 depicts a functional block diagram showing a prior-art temperature detecting system for detecting a working temperature of a chip. The temperature detecting system includes a converting circuit 10 and a thermal diode 12. The converting circuit 10 further includes an A-to-D converting unit 102 connected to the two terminals of the thermal diode 12, and a signal-to-temperature mapping unit 104 connected to the A-to-D converting unit 102. The thermal diode 12 can be designed in the chip (not shown) or attached on the chip.
A main characteristic of the thermal diode 12 is that a current flowing through the thermal diode 12 is related to the working temperature of the thermal diode 12, which means there is a specific equation between the current flowing through the thermal diode 12 and the working temperature of the chip. Basically, the current flowing through the thermal diode 12 is increasing with the working temperature of the chip. As depicted in FIG. 1, the current flowing through the thermal diode 12 varies with the working temperature of the chip if the thermal diode 12 is designed in the chip or attached on the chip. When the current is derived from the thermal diode 12, the current (an analog signal) is converted to a digital signal by the A-to-D converting unit 102, and the converted digital signal is further transmitted to the signal-to-temperature mapping unit 104. After the mapping processed by the signal-temperature mapping unit 104, a temperature corresponding to the value of the digital signal is generated, so as the working temperature of the chip is detected.
Conventionally, the temperature detecting system is implemented by both an analog circuit and a digital circuit. However, the analog circuit, compared to the digital circuit, usually takes up more layout area in a chip and also needs a more complicate circuit design.
For fixing the problems of the analog temperature detecting system taking up too much layout area in a chip and the analog circuit needing a more complicate circuit design, the present invention discloses a digital temperature detecting system and method for detecting the working temperature of a chip. Additionally, a gate delay time in the chip can be further estimated through the digital temperature detecting system and method of this present invention.